Lock nut



Aug. 2, 1938. E A, REEN 2,125,276

LOCK NUT Original Filed July 30, 1932 [N \IEN T0/{ 50 WA R0 A. Gnu/vtCZT J.

Patented Aug. 2, 1938 UNITED STATES. PATENT 1 OFFICE LOCK NUT Edward A.Green, East Cleveland, Ohio, assignor to Security Machine ProductsCompany, Wilmington, Deh, a corporation of Delaware Application July 30,1932, Serial No. 626,458 Renewed July 31, 1934 2 Claims. (Cl. 151-21)This invention relates to a combined holdin and locking nut. I

An object of the invention is to provide a holding nut, which whenapplied to a bolt will have a locking action upon the bolt threads.

A further object is to provide a holding nut wherein standard threadsare employed and the thread pitch of the nut is not deformed, but whichwhen applied to a bolt will have a lockin action upon the bolt threads.

Another object is to provide a threaded nut which will produce andmaintain a friction lock tolerances established for commercial upon abolt when applied thereto independently of bolt stress.

Another object is to provide a threaded nut, distorted with respectto'its thread pitch diameter and having high diametral resilience of arange such that the nut willreact on all bolt threads that aremanufactured within the usual commercial tolerances established forthread pitch diameters to produce and maintain a friction look upon abolt when applied thereto.

A still further object is to provide a threaded nut, such as specifiedin the object just above mentioned, which is of relatively light weightas compared to its strength for resisting rupture and, wherein itsthread and bearing values for receiving and transmitting the load arenot diminished, while it will have the usual wrenching means as comparedwith standard commercial nuts for applying, adjusting and removing thenut with respect to the bolt.

Additional and further objects of the invention will become apparenthereinafter during the detailed description that is to follow of anembodimerit of the invention.

in attaining the above enumerated objects it is proposed to provide athreaded nut having a.

' transverse section such that the nut will have high-diametralresilience and to distort the nut so that it will have a minimum threadpitch diameter substantially less than the thread pitch diameter of theminimum standard bolt to which the nut will be applied, wherefore, thenut will have uniform frictional engagement with the threads of boltswhen applied thereto, even though the threads are of varying pitch diam-;Yeters provided they are manufactured withln'the bolts.

More specifically, the objects of the invention are attained-, b'yproviding aunt in the form of a tubillar internally threaded member ofsuch ftiQSiSVtiSB Sfifitiflil as to have high diametrai Jfr'es'iilence,distorting the member to provide a minimum thread pitch diameter asspecified above and providing suitable means upon the member to give thesame the requisite strength, bearing surfaces, and wrenching surfaces.

An embodiment of the invention is illustrated in theaccompanyingdrawing, wherein,

Figure 1 is 'a fragmentary side elevational view showing the nut appliedto a bolt.

Fig. 2 is a sectional view taken substantially on line 2-2 of. Fig. 1,looking in the direction of the arrows and shows the nut in rear endele-- vation.

Fig. 3 is an elevational view of the nut taken from the front endthereof.

Fig. 4 is a sectional view taken substantially on line 4-3 of Fig. 3,looking in the direction of the arrows, the diametral distortion of thenut being exaggerated.

Fig. 5 is an irregular sectional view taken'substantially on line 5-5 ofFig. 3, looking in the direction of the arrowathe diametral distortionof the nut being exaggerated.

' Fig. 6 is a diagrammatic end view of the nut transverse section ofsuch thickness-as to be 3 capable of possessing high diametralresilience. The member I 0 is provided exteriorly with a plurality ofradial fins ii that extend the full axial length of the member'and havetheir outer ends terminating in the outline of a standard nut. In thedrawing, the nut is illustrated as having a hexagonal outline, but itwill be fully understood that thenut might have a square, round or otherform of. outline, as desired to provide the necessary wrenchingsurfaces. The, fins l2 reinforce the tubular member l0 and hold ormaintain the thread spirals together in the proper position. The fins l2and the end of the member in at the rear of the nut provide an amplebearing surface for transferring theload stress when the nut is appliedto a bolt and is screwed down into the proper position thereon. Theforward ends of the longer fins I! may be chamfered, as indicated at N,as is usual in nut construction.

The threads H are formed in the member in eter, changing the circularmember and the opening therein into ah oval member and opening. Thisdistoftion is scarcely discernible to Ithe eye and, therefore, Figs. 2and'li of the drawing do not clearly illustrate the same. However,referen-ee should be had 150 Fig. 6, wherein the circular 7 form of themember or opening isjtherein indithe member Ill, aswell as the strengththereof,

the member may be suitably heat treatedafter, its distortion, asreferred to abofge.

treating of the member, addition to increasing its strength anddiahretral resilience, alsov mercial nuts.

one diametral line, acts when 65' serves to prevent the thread surfacesof the member and of the belt towhich'it is applied, fromseizingfjzluring the application to and the removal of the nut Irom thebolt. That is to say, the heat treated and hardened nut functions in thenature of a die and will be eg'fective to cor,- re'ct imperfect threadsupon the h'olt.

In Figs. 4 and 5 ct the drawlngi the diametral distortion of the.nut iseg-iaggerated to illustrate that such distortion does not have to beuniform from end to endfof the nut,but that it may be desirable 'todistrt the nut to a greater extent i adjacentfits outer end than at itsinner end to permit the nut to more easily take the threads or the boltand to thus facilitate its appiication thereto. 'It should beunderstood, however, that the distortion of the nut might hle uniformfrom end to end and probably 'would be, except in the case of nuts ofvery small size and extremely fine threads, where it would be desirableto providethe non-unifornf distortion referred to above.

It is proposed? to construct the nut from ha? stock, sri'ch as specialsections of cold drawn steel will expfand'along its minimum diameter andThe heat standard nut only has eflicient frictional locking adapt itselfto the bolt, while, because its in-' herent lhametral resilience it willhave 3; tendency to return to oval form and. will, therefore,frictionally engage or interlock" with the bolt threads at diametricallyopposite points alongits minimum thread piteh diameter. It will be notedthat, since the member possesses a high range of diametral resilience,it will be capable of making the necessary diametral adjustments to fitali threads of varying pitch diameters uponj jeolts manufactured withinthe tolerances established for commercial bolts. If the nut'jis oper Illating under a light load there can be no further expansion in itsminimum dianieter, other than that caused by its application to thebolt, but ,should the load, transmitted-through the angularly disposedsurfaces of the threads, exceed the resistance of the nut to diametraldistortion, the nut be expanded in its minor diameter and contracted inits major diameter until it becomes substantially round. However, uponthe reduc tion of the bolt tension, either because of the stretch of thebolt or the wear of the several surfaces of contact thereof, or'iorother reasons, the nut will, due to itsinherent diametral resilience,return to its oval ionn and efiectively "grasp the boltfjhreadsjfornutlocking purposes. "Thereifore, there will be at all times and under allconditions effective resistance to the turning oi. the nut on the bolt.On the .othe'r hand, a

effect with the bolt threads unfgler, maximum bolt tension, that is, thelocking efiectof a standard nut is in direct propcrtion to the boltstress of tension. 1 7

It is appreciated that a nut constructed in accordance with the presentinvention will be somewhat weaker than a nut of standard. de-

sign when made of the same material, but it' 'is 40 proposed to form thenuts of a material difierent from that ordinari'iy'used in nutmanufacture and it will be noted that the nut is so designed andcapableof being heat treated to a substanthat it may be economically producedin such manner and by the usual methods of production employed in themanufacture of standard com- The bar stock may be formed in the desiredshape, that is hexagonal, square, or any other de sired polygonal"shape, and is'then provided with tially greater tensile strengtlr.Also, if the loss of bearing surface, due to the resilient design of thenut is material, such loss may be compenexterior fins. running thelongitudinal lengtli It will be noted that the nut of the presentinthereof 'and having their outer ends terminating in the desiredhexagonal or other polygonal shape, (see Fig. *1). The bar stoclris thendrilled and severed to form to the separate nut blanks, after which thesevered blanks are tapped, then distorted along a diametral line aspreviously mentioned, and then heat treated to give thenut the desireddiametral resilience.

The manner in which a nut, formedas specified above, that is a nut inthe form of a tubular member having a section such as to possess highdiametral resilience and being distorted along applied to a bolt willnow be described.

Whenthe nut is applied to a bolt it will have a tight or interferencefit thereon due to the diametral distortion of the nut to provide aminimum thread pitch diameter less than the minimum thread pitchdiameter of the standard bolt with which the nut is to be. used.However, since the tubular member forming the nut possesses highdiametral resilience and sin e the member, was originally tapped to havea tree fit upon the boltgit will be seen that the member ventien isoi'extremely lightweight per unit of rapidly'with the length of time andservice. it

will iurtherbe noted that a nut constructed, as specified abeve, retainsall the essential features of a standard commercial nut as to strength;bearing'values of thread and base, standard threads and provision forwrenching, while at the same. I

time, because of its section designed to possess" high diametralresilience and because of its distortion to provide a mlniminn threadpitch diam eter, it will have uniform frictional grasping or lookingengagement with the threads of a bolt when applied to threads oi varyingthread pitch '5 should be understood that the invention is susceptibleof various modifications and adaptations within the scope of theappended claims.v

Having thus described my invention. I claim: l. A combined holding andlocking nut com- 10 prising, x a substantially completely internallythreade tubular member oi a transverse section such that the member isdiametrally resilient and being pro'vided with a. plurality of exteriorradially 1 projecting axially extending has the outer ends of 16 whichterminate in the outline of a standard nut to furnish wrenchingsurfaces. said member being diametrally distorted substantially from endto end thereof to have a minimum thread pitch diameter less than theminimum thread pitch diameter of any standard bolt with which it wouldbe 2.- A combined holding .and'locking nut comprlsing a diametrallyresilient internally threaded tubular member having an exterior outlinecorresponding to that of a standard nut to provide wrenching surfacesand provided around its perimeter with a plurality of circumierentiallyspaced inwardly extending slots whereby stiiiening angles in thetransverse section of the member are eliminated, said memberbeing-diametrally distorted to have a minimum thread pitchdiameter lessthan the minimum thread pitch diameter of any standard bolt with ,whichit would be used.

. EDWARD A. GREEN.

